Maria Sharapova, ranked No. 2 on the WTA Tour, will return to Japan next month to play in the Pan Pacific Open. Sharapova, who won the Pan Pacific title in 2005, will be among three top-10 players in the Jan. 30-Feb. 4 event at Tokyo Metropolitan Gymnasium, tournament organizers announced Thursday. Martina Hingis, who is seventh in the world rankings, and defending champion and eighth-ranked Elena…